In vitro regeneration and acclimatization protocols of selected ornamental plants (agapanthus praecox, justicia betonica and celosia cristata)

This paper discussed on the effectiveness of BAP and NAA growth hormones on establishment of plant regeneration for selected ornamentals; Agapanthus praecox, Justicia betonica and Celosia cristata. Various explants (leaf, stem, shoot tip and bulb) derived from one-month-old aseptic seedlings of A. praecox and C. cristata, as well as explants from intact plants of J. betonica were utilized to achieve complete plant regeneration of these species. MS medium supplemented with various hormones, with an emphasis on BAP and NAA was tested to obtain direct and indirect regeneration. Both A. praecox (bulbs) and C. cristata (shoots) formed complete plantlets on MS added with 0.5-2.0 mg/L BAP and NAA, while direct regeneration was achieved for J. betonica on MS media containing BAP. Several methods were attempted to acclimatize the regenerants, with A. praecox gave the highest percentage of survival rates (96.67%), followed by J. betonica (80.00%) and C. cristata (75.00%)

Estudio de organogénesis, morfología y anatomía en el Baybean (Canavalia rosea (Sw.) DC.)

Morphological and anatomical studies comprised leaf venation, histological analysis and epidermal peeling were carried out on Canavalia rosea (Sw.) DC.). Anatomical studies of the leaf and root determined the presence of cuticle and oil glands, arrangement of cells and the structure of vascular system. The dorsiventral leaf with pinnate venation and amphistomatic leaf with paracytic type stomata were embedded below the epidermis. Trichomes and oil glands were also observed on both adaxial and abaxial surfaces of leaf. Longitudinal sections of the callus showed the existence of meristematic cells, which could give rise to plant regeneration. In the process of organogenesis, adventitious shoots emerged from leaf and stem explants within 2 months after culturing on MS media fortified with 6-Benzylaminopurine (1.0-2.0 mg/l). Ultimately, in vitro germination was successfully established for the propagation and future conservation programs of this species.Se realizaron estudios morfológicos y anatómicos de venación foliar, análisis histológico y peeling epidérmico en Canavalia rosea (Sw.) DC). Los estudios anatómicos de la hoja y de la raíz determinaron la presencia de la cutícula y de las glándulas de aceite, la disposición de células y la estructura del sistema vascular. La hoja dorsiventral con venación pinnada y la hoja anfistomática con estomas paracíticos estaban incrustados debajo de la epidermis. También se observaron tricomas y glándulas oleosas en las superficies adaxial y abaxial de la hoja. Las secciones longitudinales del callo mostraron la existencia de células meristemáticas que podrían dar lugar a la regeneración de las plantas. En el proceso de organogénesis, brotes adventicios surgieron de los explantes de hoja y tallo en los 2 meses después del cultivo en medios de MS fortificados con 6-bencilaminopurina (1,0-2,0 mg / l). En última instancia, la germinación in vitro se estableció con éxito para la propagación y los futuros programas de conservación de esta especie

Optimization of Culture Conditions (Sucrose, pH, and Photoperiod) for In Vitro

Various explants (stem, leaf, and root) of Citrus assamensis were cultured on MS media supplemented with various combinations and concentrations (0.5–2.0 mgL−1) of NAA and BAP. Optimum shoot and root regeneration were obtained from stem cultures supplemented with 1.5 mgL−1 NAA and 2.0 mgL−1 BAP, respectively. Explant type affects the success of tissue culture of this species, whereby stem explants were observed to be the most responsive. Addition of 30 gL−1 sucrose and pH of 5.8 was most optimum for in vitro regeneration of this species. Photoperiod of 16 hours of light and 8 hours of darkness was most optimum for shoot regeneration, but photoperiod of 24 hours of darkness was beneficial for production of callus. The morphology (macro and micro) and anatomy of in vivo and in vitro/ex vitro Citrus assamensis were also observed to elucidate any irregularities (or somaclonal variation) that may arise due to tissue culture protocols. Several minor micromorphological and anatomical differences were observed, possibly due to stress of tissue culture, but in vitro plantlets are expected to revert back to normal phenotype following full adaptation to the natural environment

Physiological Responses of Callus from Gerbera jamesonii Bolus ex. Hook f. to Gamma Irradiation

In the present study, in vitro mutagenesis techniques were applied to investigate the effects of gamma irradiation at 0, 10, 20, 30, 40, 50 and 60 Gy on physiological changes in callus of Gerbera jamesonii Bolus ex. Hook f. Biochemical changes in chlorophyll and soluble protein content of pre- and post- irradiated Gerbera callus were studied. Non-irradiated callus demonstrated the highest amount of chlorophyll content as compared to callus irradiated at 10, 20, 30, 40, 50 and 60 Gy. In addition, the amount of chlorophyll b was relatively higher than chlorophyll a in both the irradiated and non-irradiated callus, except for callus irradiated at 10 Gy. Biochemical differentiation based on total soluble protein content revealed gradual reduction after day 9 of exposure to gamma irradiation. Reduction of soluble protein content was observed in all the treatments as the increase of incubation period